U.S. patent number 10,232,543 [Application Number 15/301,244] was granted by the patent office on 2019-03-19 for thickness variation-adjusting air ring.
This patent grant is currently assigned to SHONAN TRADING CO., LTD.. The grantee listed for this patent is SHONAN TRADING CO., LTD.. Invention is credited to Norio Hashimoto, Akira Shimizu.
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United States Patent |
10,232,543 |
Shimizu , et al. |
March 19, 2019 |
Thickness variation-adjusting air ring
Abstract
Provided is a thickness variation adjustment-type air ring
capable of accurately and optimally controlling the volume of
cooling air at all positions in the circumferential direction, and
stably manufacturing a synthetic resin film having an exceptionally
low thickness variation. A thickness variation adjustment-type air
ring is provided on a die of an inflation film manufacturing
apparatus which locally controls the volume of cooling air
discharged from a cooling air passage in a circumferential
direction to adjust the thickness variation of a synthetic resin
film when blowing the cooling air around a molten synthetic resin
tube extruded in a longitudinal direction to cool and solidify the
molten synthetic resin tube to form the synthetic resin film, the
thickness variation adjustment-type air ring. The thickness
variation adjustment-type air ring includes: a ring-shaped passage
adjustment portion arranged sequentially in the circumferential
direction inside of the cooling air passage; and a plurality of
moving portions connected at a predetermined position in the
circumferential direction of the passage adjustment portion so as
to move a connecting portion of the passage adjustment portion in a
predetermined direction independently from other portions, wherein
a space in which cooling air can circulate inside the cooling air
passage is locally adjusted in the circumferential direction and
the volume of cooling air is locally controlled in the
circumferential direction.
Inventors: |
Shimizu; Akira (Sagamihara,
JP), Hashimoto; Norio (Yokohama, JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
SHONAN TRADING CO., LTD. |
Yokohama-shi |
N/A |
JP |
|
|
Assignee: |
SHONAN TRADING CO., LTD.
(Yokohama-Shi, Kanagawa, JP)
|
Family
ID: |
52139040 |
Appl.
No.: |
15/301,244 |
Filed: |
March 18, 2015 |
PCT
Filed: |
March 18, 2015 |
PCT No.: |
PCT/JP2015/057986 |
371(c)(1),(2),(4) Date: |
September 30, 2016 |
PCT
Pub. No.: |
WO2015/159634 |
PCT
Pub. Date: |
October 22, 2015 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20170015043 A1 |
Jan 19, 2017 |
|
Foreign Application Priority Data
|
|
|
|
|
Apr 14, 2014 [JP] |
|
|
2014-083122 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B29C
48/10 (20190201); B29C 55/28 (20130101); B29C
48/913 (20190201); B29C 48/92 (20190201); B29C
2948/92447 (20190201); B29L 2023/001 (20130101); B29C
2948/926 (20190201); B29C 2948/92971 (20190201); B29C
2948/92657 (20190201); B29C 2948/92152 (20190201); B29K
2105/0067 (20130101) |
Current International
Class: |
B29C
55/28 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
3743720 |
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Sep 1989 |
|
DE |
|
3743720 |
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Sep 1989 |
|
DE |
|
42 18 997 |
|
Jan 1994 |
|
DE |
|
1 004 424 |
|
May 2000 |
|
EP |
|
854368 |
|
Nov 1960 |
|
GB |
|
S54-64173 |
|
May 1979 |
|
JP |
|
S 56-164824 |
|
Dec 1981 |
|
JP |
|
S 58-28823 |
|
Jun 1983 |
|
JP |
|
S 59-015518 |
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Jan 1984 |
|
JP |
|
H 05-269844 |
|
Oct 1993 |
|
JP |
|
H 07-205279 |
|
Aug 1995 |
|
JP |
|
2004-276505 |
|
Oct 2004 |
|
JP |
|
2009-269382 |
|
Nov 2009 |
|
JP |
|
Other References
International Search Report (ISR) (PCT Form PCT/ISA/210), in
PCT/JP2015/057986, dated Apr. 21, 2015. cited by applicant .
Octagon Process Technology GmbH, "Automatically Controlled air ring
SmartLip DL," [Online], Retrieved on Apr. 11, 2014, Internet:
http://octagon-gmbh.de/uploads/PDF/prospektdownloads/englisch/SmartLip-DL-
_e.pdf#search=`smartlipdl_e+V1.1.odt%2F05.12`. cited by applicant
.
Extended European Search Report dated Sep. 19, 2017 in European
Application No. 15779799.4. cited by applicant .
Chinese Office Action dated Feb. 23, 2018 in Chinese Application
No. 201580018984.9 with an English translation thereof. cited by
applicant .
Chinese Office Action, dated Sep. 20, 2018 in Chinese Application
No. 201580018984.9 and English Translation thereof. cited by
applicant.
|
Primary Examiner: Minskey; Jacob T
Assistant Examiner: Williams; Cedrick S
Attorney, Agent or Firm: McGinn I.P. Law Group, PLLC.
Claims
The invention claimed is:
1. A thickness variation adjustment-type air ring which is provided
on a die of an inflation film manufacturing apparatus which locally
controls a volume of cooling air discharged from a cooling air
passage in a circumferential direction to adjust a thickness
variation of a synthetic resin film when blowing the cooling air
around a molten synthetic resin tube extruded in a longitudinal
direction to cool and to solidify the molten synthetic resin tube
to form the synthetic resin film, the thickness variation
adjustment-type air ring comprising: a ring-shaped passage
adjustment portion arranged sequentially in the circumferential
direction inside of the cooling air passage; and a plurality of
moving portions connected at a predetermined position in the
circumferential direction of the passage adjustment portion so as
to move a connecting portion of the passage adjustment portion in a
predetermined direction independently from other portions, wherein
the cooling air passage is substantially closed and not divided,
wherein the passage adjustment portion includes a ring-shaped
elastic member formed sequentially in the circumferential
direction, wherein the cooling air passage includes a groove in
which the ring-shaped elastic member is placed, wherein a moving
portion of the moving portions moves a connecting portion of the
elastic member in the longitudinal direction of the molten
synthetic resin tube, and wherein a space in which the cooling air
is configured to circulate inside the cooling air passage is
locally adjusted in the circumferential direction and the volume of
cooling air is locally controlled in the circumferential
direction.
2. The thickness variation adjustment-type air ring according to
claim 1, wherein the moving portion includes an air cylinder.
3. The thickness variation adjustment-type air ring according to
claim 2, wherein the moving portion further includes a rod portion
which moves in the longitudinal direction of the molten synthetic
resin tube, and wherein the elastic member is attached to the rod
portion.
4. The thickness variation adjustment-type air ring according to
claim 3, wherein the moving portion further includes a coil spring
applying a force to the rod portion.
5. The thickness variation adjustment-type air ring according to
claim 1, wherein the elastic member is attached to a rod portion of
the moving portion which moves in the longitudinal direction of the
molten synthetic resin tube.
6. The thickness variation adjustment-type air ring according to
claim 1, wherein the moving portion includes: a rod portion which
moves in the longitudinal direction of the molten synthetic resin
tube; and a coil spring applying a force to the rod portion.
7. The thickness variation adjustment-type air ring according to
claim 1, wherein the ring-shaped elastic member has an endless
structure.
8. The thickness variation adjustment-type air ring according to
claim 1, wherein the ring-shaped elastic member is free of gaps in
between joints.
Description
TECHNICAL FIELD
The present invention relates to a thickness variation
adjustment-type air ring which is provided on a die of an inflation
film manufacturing apparatus that forms a synthetic resin film so
as to locally control the volume of cooling air in a
circumferential direction in order to adjust the thickness
variation (thickness unevenness) of a synthetic resin film when
blowing the said cooling air around an extruded molten synthetic
resin tube to cool and solidify the molten synthetic resin tube to
form the synthetic resin film.
BACKGROUND ART
A general inflation film manufacturing apparatus forms a synthetic
resin film by cooling and solidifying a molten synthetic resin tube
extruded from a die slit (for example, see Patent Document 1). The
inflation film manufacturing apparatus of Patent Document 1
includes a die head having a ring nozzle, an outer blowing nozzle
and a measurement device for measuring the film thickness of
tube-shaped film. The volume of air flow passing through the
nozzles of the ring of the air nozzle group is controlled based on
the measurement results of the measurement device.
Moreover, an inflation film manufacturing apparatus which controls
the thickness variation of a synthetic resin film by creating a
difference in the volume of cooling air locally in the
circumferential direction is proposed (for example, see Non-Patent
Document 1). An air ring illustrated in FIGS. 9 to 11, for example,
is known as an example of an air ring used in this type of
inflation film manufacturing apparatus. As illustrated in FIG. 9, a
number of block-shaped slope members are arranged in a ring form in
a cooling air passage inside of an air ring 100. The slope members
101 are moved in a radial direction by a moving portion 107 such as
a motor, to locally change the gap of passages 103 formed between
the slope members 101 and a blow out ring 102. In this way, it is
possible to locally control the volume of cooling air directed to a
molten synthetic resin tube 104 in a circumferential direction. In
FIGS. 9 and 10, reference numeral 105 indicates a hose opening,
through which cooling air 106 from a blower (not illustrated) is
introduced via a hose (not illustrated) connected to the hose
opening 105. In the illustrated example, the hose opening 105 has
four hose openings separated at a predetermined interval in the
circumferential direction.
CITATION LIST
Patent Document
Patent Document 1: Japanese Unexamined Patent Application,
Publication No. H5-269844
Non-Patent Document 1: Octagon Process Technology GmbH,
"Automatically Controlled air ring SmartLip DL," [Online],
Retrieved on Apr. 11, 2014, Internet
<http://octagon-gmbh.de/uploads/PDF/prospektdownloads/englisc-
h/SmartLip-DL_e.pdf#search=`smartlipdl_e+V1.1.odt%2F05.12`>
DISCLOSURE OF THE INVENTION
Problems to be Solved by the Invention
However, in the air ring 100 having the above-described
configuration, it is necessary to form a gap 108 between each
adjacent slope member 101 in order to move any slope member 101 in
the radial direction. If the grip portion 108 is not present, the
respective slope members 101 may block each other's way and may not
move toward the inner side of the radial direction from their
positions. Moreover, even if it is set so that there be no gap 108
between each slope member 101 on the inner side of the radial
direction, although the slope members 101 will still be able to
move toward the outer side in the radial direction, the gap 108
will be formed when the slope members move toward the outer side of
the radial direction.
In a structure which has the gap 108 as described above, the flow
of cooling air is disturbed as indicated by flow lines 109 in FIG.
9. Moreover, although the cooling airflowing through portions other
than the gap 108 is controlled by each of the slope members 101,
the cooling air, flowing through the gap 108, flows regardless of
the gap of the passage 103 formed by the slope members 101, and for
this reason it is not possible to control the cooling air flowing
through the gap 108. Since the thickness variation of a synthetic
resin film depends on the flow conditions such as the volume of
cooling air, the problem of having parts of the synthetic resin
film whose thickness variation is not possible to control,
occurs.
With the foregoing in view, the objective of the present invention
is to provide a thickness variation adjustment-type air ring
capable of accurately and optimally controlling the volume of
cooling air at all positions in the circumferential direction and
stably manufacturing a synthetic resin film having an exceptionally
low thickness variation.
Means for Solving the Problems
In order to attain the aforementioned objective, the present
invention provides a thickness variation adjustment-type air ring
which is provided on a die of an inflation film manufacturing
apparatus and which locally controls the volume of cooling air
discharged from a cooling air passage in a circumferential
direction to adjust the thickness variation of a synthetic resin
film when blowing the said cooling air around a molten synthetic
resin tube extruded in a longitudinal direction to cool and
solidify the molten synthetic resin tube to form the synthetic
resin film, the thickness variation adjustment-type air ring
comprising: a ring-shaped passage adjustment portion arranged
sequentially inside the cooling air passage in the circumferential
direction; and a plurality of moving portions connected at a
predetermined position in the circumferential direction of the
passage adjustment portion so as to move a connecting portion of
the passage adjustment portion in a predetermined direction
independently from other portions, wherein a space in which the
cooling air can circulate inside the cooling air passage is locally
adjusted in the circumferential direction and the volume of cooling
air is locally controlled in the circumferential direction.
In the thickness variation adjustment-type air ring, the passage
adjustment portion may be formed of a ring-shaped elastic member
formed sequentially in the circumferential direction.
In the thickness variation adjustment-type air ring, the moving
portion may move a connecting portion of the elastic member in the
longitudinal direction of the molten synthetic resin tube.
In the thickness variation adjustment-type air ring, the moving
portion may move a connecting portion of the elastic member in the
radial direction of the molten synthetic resin tube.
In the thickness variation adjustment-type air ring, the passage
adjustment portion may be formed of a plurality of movable members
which are arranged in a ring form without any gap in the
circumferential direction and can move in the longitudinal
direction of the molten synthetic resin tube.
In the thickness variation adjustment-type air ring, the moving
portion may move the movable member in the longitudinal direction
of the molten synthetic resin tube.
Advantages of the Invention
According to the present invention, it is possible to accurately
and optimally control the volume of cooling air at all positions in
the circumferential direction and stably manufacture a synthetic
resin film having an exceptionally low thickness variation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of a schematic configuration of an inflation
film manufacturing apparatus illustrating a first embodiment of the
present invention.
FIG. 2 is a schematic cross-sectional view of the inflation film
manufacturing apparatus surrounding a thickness variation
adjustment-type air ring.
FIG. 3 is a cross-sectional view taken along arrows A-A in FIG.
2.
FIG. 4 is a cross-sectional view taken along arrows B-B in FIG.
2.
FIG. 5 is a schematic cross-sectional view of an inflation film
manufacturing apparatus surrounding a thickness variation
adjustment-type air ring illustrating a second embodiment of the
present invention.
FIG. 6 is a cross-sectional view taken along arrows C-C in FIG.
5.
FIG. 7 is a planar cross-sectional view of a thickness variation
adjustment-type air ring illustrating a third embodiment of the
present invention.
FIG. 8 is a side cross-sectional view of a thickness variation
adjustment-type air ring.
FIG. 9 is a planar cross-sectional view of a conventional thickness
variation adjustment-type air ring.
FIG. 10 is a cross-sectional view taken along arrows D-D in FIG.
9.
FIG. 11 is a cross-sectional view taken along arrows E-E in FIG.
9.
PREFERRED MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a plurality of embodiments of a thickness variation
adjustment-type air ring according to the present invention will be
described in detail with reference to the drawings.
FIGS. 1 to 4 illustrate a first embodiment of the present
invention, in which FIG. 1 is a diagram illustrating a schematic
configuration of an inflation film manufacturing apparatus, FIG. 2
is a schematic cross-sectional view of the inflation film
manufacturing apparatus surrounding a thickness variation
adjustment-type air ring, FIG. 3 is a cross-sectional view taken
along arrows A-A in FIG. 2, and FIG. 4 is a cross-sectional view
taken along arrows B-B in FIG. 2.
As illustrated in FIG. 1, in an inflation film manufacturing
apparatus 1, a molten synthetic resin 3a supplied to a die 2 by an
extruder (not illustrated) is extruded from a die slit 2a as a
molten synthetic resin tube 3. The extruded molten synthetic resin
tube 3 is thinly stretched in both left and right radial directions
and is cooled by cooling air 5 from a blower (not illustrated),
whereby a tubular synthetic resin film 3b is obtained. The
synthetic resin film 3b is drawn by a pinch roll 6 and is wound
around a winding machine (not illustrated). Air having a
predetermined pressure is sealed inside the molten synthetic resin
tube 3 (the tubular synthetic resin film 3b).
Moreover, the inflation film manufacturing apparatus 1 includes a
thickness variation adjustment-type air ring 4 which is provided on
the die 2 so as to locally control the volume of the cooling air 5
discharged from a cooling air passage 48 (see FIG. 2) into the
circumferential direction to adjust the thickness variation of the
synthetic resin film 3b when blowing the cooling air 5 around the
molten synthetic resin tube 3 extruded in the longitudinal
direction to cool and solidify the molten synthetic resin tube 3 to
form the synthetic resin film 3b.
Moreover, a thickness sensor 7 that measures the thickness of the
tubular synthetic resin film 3b is provided on an upstream side of
the pinch roll 6. The thickness sensor 7 is, for example, an
electrostatic capacitance-type sensor, a laser-type sensor, or the
like, in which a detection signal related to thickness variation
information of the synthetic resin film 3b is input from the
thickness sensor 7 into a control unit 8 which is formed as a
computer or the like.
The control unit 8 modulates a ring-shaped passage adjustment
portion arranged sequentially inside the cooling air passage 48 of
the air ring 4 in the circumferential direction with the aid of a
moving portion, based on the thickness variation information of the
synthetic resin film 3b, obtained from the detection signal of the
thickness sensor 7, to thereby locally control the volume of the
cooling air 5 flowing through the cooling air passage 48 in the
circumferential direction so that the thickness variation of the
synthetic resin film 3b is decreased and equalized.
In the present embodiment, as illustrated in FIG. 2, the air ring 4
is disposed horizontally and has a ring shape such that the inner
side in the radial direction of the upper surface thereof is
depressed. Moreover, the air ring 4 has a ring-shaped blow out
opening 45 formed in an inner circumferential portion and is fixed
to the die 2 by suitable means so as to be concentric with respect
to the ring-shaped die slit 2a of the die 2.
A cooling air trapping portion 44 is formed on the outer side in
the radial direction inside the air ring 4 by a ring-shaped
rectification plate 46. In the present embodiment, four hose
openings 40 are formed in the cooling air trapping portion 44
separated at equal intervals in the circumferential direction, and
the cooling air 5 from the blower (not illustrated) is introduced
through hoses connected to these hose openings 40.
The cooling air passage 48 connected to the cooling air trapping
portion 44 is formed on the inner side in the radial direction
inside the air ring 4, and a ring-shaped elastic member 41 formed
sequentially in the circumferential direction is installed in the
cooling air passage 48. In the present embodiment, the elastic
member 41 forms a ring-shaped passage adjustment portion arranged
sequentially in the circumferential direction inside of the cooling
air passage 48. As illustrated in FIGS. 3 and 4, rod portions of a
plurality of air cylinders 43 arranged in line in the
circumferential direction are connected to the elastic member 41.
In the present embodiment, each air cylinder 43 forms a moving
portion that is connected to a predetermined position in the
circumferential direction of the passage adjustment portion so as
to move the connecting portion of the passage adjustment portion in
a predetermined direction independently from the other portions.
Moreover, a coil spring 42 is attached to the rod portion of the
air cylinder 43 so as to oppose the movement of the rod.
The cooling air 5 from the blower (not illustrated) is distributed
to four hoses and is introduced into the cooling air trapping
portion 44 on the outer side of the air ring 4 from the hose
opening 40. The cooling air 5 is rectified to a uniform flow toward
the center in the radial direction while winding its way up and
down through the rectification plates 46 and 47 and is discharged
from the blow out opening 45 toward the molten synthetic resin tube
3. In this way, the cooling air passage 48 extends in the radial
direction of the molten synthetic resin tube 3, and each air
cylinder 43 moves the connecting portion of the elastic member 41
in the longitudinal direction of the molten synthetic resin tube 3
(that is, in the direction running vertical to the extension
direction of the cooling air passage 48). Here, a width of the
cooling air passage 48 is between 3 mm and 50 mm, for example.
Since the elastic member 41 having an endless structure does not
have gaps formed in between joints, etc., the cooling air 5
rectified by the rectification plates 46 and 47 and the like is not
disturbed by the elastic member 41. Moreover, it is possible to
locally adjust the space in which the cooling air 5 can circulate
inside the cooling air passage 48 with the aid of the elastic
member 41 and to reliably control the volume of the cooling air 5
at all positions in the radial direction.
Here, since the solidified portion of the molten synthetic resin
tube 3 extruded from the die slit 2a is stretched and does not
become thinner any more, portions which are not solidified are
stretched and become thinner. Therefore, when the volume of the
cooling air 5 corresponding to the thick portion in the
circumferential direction of the tubular synthetic resin film 3b is
decreased, the cooling and solidification of the portion of the
molten synthetic resin tube 3 is delayed and thus the portion
becomes thinner, rendering it possible to control the thickness
variation of the synthetic resin film 3b.
When an air pressure 49 supplied to the air cylinder 43
corresponding to the thick portion of the tubular synthetic resin
film 3b is increased by the control unit 8 based on the thickness
variation information of the thickness sensor 7, the cooling air
passage 48 narrows since the air cylinder 43 moves the elastic
member 41 in a vertical direction in relation to a horizontal
surface up to a position that matches the force of the coil spring
42. As a result, the volume of air supplied to the thick portion
decreases, the corresponding portion of the molten synthetic resin
tube 3 becomes thinner, and a uniform tubular synthetic resin film
3b whose thickness variation is low is obtained.
Since it is difficult to deform the elastic member 41 if the
elastic member 41 is too hard, rubber having hardness of 70.degree.
(JIS-A) is preferred. Moreover, the elastic member 41 may be
adjusted using a stepping motor or the like instead of the air
cylinder 43 and may be adjusted manually by a bolt or the like.
According to the thickness variation adjustment-type air ring 4
having the above-described configuration, since it is not necessary
to form a gap in the circumferential direction and it is possible
to control the thickness variation locally and to control the
cooling air at all positions in the circumferential direction, it
is possible to form a uniform synthetic resin film 3b whose
thickness variation is low.
The air ring 4 of the inflation film manufacturing apparatus 1 of
the first embodiment was manufactured and tested. When a five-hour
long continuous operation was performed under manufacturing
conditions such that LLDPE having the MRF of 1 was used as the raw
material for the molten synthetic resin 3a, a tube having a 1000 mm
diameter and a tube whose thickness was 50 .mu.m were used, and
where the drawing speed was 23 m/minute, a synthetic resin film 3b
whose thickness variation was between .+-.5.7% and .+-.6.4% (the
thickness unevenness was based on average thickness) was
obtained.
FIGS. 5 and 6 illustrate a second embodiment of the present
invention, in which FIG. 5 is a schematic cross-sectional view of
an inflation film manufacturing apparatus and FIG. 6 is a
cross-sectional view taken along arrows C-C in FIG. 5.
In the first embodiment, although the elastic member 41 is moved in
the longitudinal direction of the molten synthetic resin tube 3,
the moving direction of the passage adjustment portion may be set
arbitrarily. In the second embodiment, as illustrated in FIGS. 5
and 6, the air cylinder 43 moves the connecting portion of the
elastic member 51 in the radial direction of the molten synthetic
resin tube 3 to locally adjust the gap of the cooling air passage
58 as well as to locally adjust the volume of cooling air, thereby
controlling the thickness variation of the synthetic resin film
3b.
FIGS. 7 and 8 illustrate a third embodiment of the present
invention, in which FIG. 7 is a planar cross-sectional view of a
thickness variation adjustment-type air ring and FIG. 8 is a side
cross-sectional view of the thickness variation adjustment-type air
ring.
In the present embodiment, the passage adjustment portion is formed
as a plurality of movable members 61 which are arranged in a ring
form without any gap in the circumferential direction and can move
in the longitudinal direction of the molten synthetic resin tube 3.
Since the movable members 61 can move the air cylinder 43 in a
vertical direction in relation to a horizontal surface and no gap
is formed between the movable members 61, the flow of the cooling
air 5 is not disturbed, and it is possible to locally control the
cooling air 5 as intended at all positions.
While embodiments of the present invention have been described, the
embodiments described above do not limit the invention described in
the claims. Moreover, it is to be noted that not all combinations
of the features described in the embodiment are necessarily
indispensable for solving the problems intended to be solved by
this invention.
INDUSTRIAL APPLICABILITY
The thickness variation adjustment-type air ring of the present
invention can accurately and optimally control the volume of
cooling air at all positions in the circumferential direction and
stably manufacture a synthetic resin film having an exceptionally
low thickness variation.
EXPLANATION OF REFERENCE NUMERALS
1: Inflation film manufacturing apparatus
2: Die
2a: Die slit
3: Molten synthetic resin tube
3a: Molten synthetic resin
3b: Synthetic resin film
4: Air ring
5: Cooling air
7: Thickness sensor
8: Control unit
40: Hose opening
41: Elastic member
42: Coil spring
43: Air cylinder
45: Blow out opening
46: Rectification plate
47: Rectification plate
48: Cooling air passage
51: Elastic member
58: Cooling air passage
61: Movable member
100: Air ring
101: Slope member
102: Blow out ring
103: Passage
104: Molten synthetic resin tube
105: Hose opening
106: Cooling air
107: Moving portion
108: Gap
* * * * *
References